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A light and portable magnetic loop antenna with improved bandwidth and performance by HB9MTN

A magnetic loop antenna using a 28\" bicycle rim for six meter band

A magnetic loop antenna for 7 Mhz by ZL1BJQ

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

Although a magnetic loop antenna(aka small loop antenna) is very compact, its efficiency is close to a half-wavelength dipole if carefully built.

Drawing and plan for an HF magnetic loop antenna

Magnetic Loop antenna for broadcasts band reception

This max size magnetic loop antenna for 14 MHz with a totall circumference of 6m is designed to attach to a wall

A homebrew Magmount for 2m antenna

Detection and recording of Schumann resonances and other electromagnetic phenomena at frequencies below 50 Hz By Hans Michlmayr

This ia a home built Magnetic loop antenna which was used by G3BGR, indoors on 7,10 and 14Mhz. The basic idea was in Radcom 1986

VK3YE magnetic loop antenna plan that cover 7 Mhz to 20 Mhz and shortening loop can work on 21 Mhz.

A complete guide to magnetic loop antenna construction, with analysis of multi-turn and single-turn magneti loops, and and insight on choosing the optimal capacitor, or homebrewing your own butterfly capacitor

A switchable Magnetic Transformer for Transmitting for various impedances

A magnetic loop antenna working from 30 to 15 meters with 100W

An Experimental, High-efficiency, Graphic-Tunable Magnetic Loop antenna and loop controller in a 52 pages PDF presentation with drawings and pictures

Article about small magnetic loop antennas with notes on realization of magnetic loops for several HF bands and the six meter band

An home made magnetic loop antenna project using a military surplus 150pf capacitor by KF5CZO

A monster magnetic loop antenna for 160 meters band. This Magnetic loop is optimized for 1840 Khz + 50 Khz. PDF Article published on La Radiospecola 10.22

Here is a well documented plan of a 20m-10m compact magnetic loop antenna. Article includes lots of pictures and technical details published by KP4MD

DL7JV Christian report his direct experience on magnetic antennas

Windows Magnetic Loop antenna design software by DG0KW in Detusch

A system designed to automatically tune small transmitting magnetic loop antennas, particularly beneficial for **contest operations** where rapid frequency changes are common. The core of the system involves a PC-based control application, AutoCap, written in C#, which monitors antenna SWR via an external meter and commands a motor interface to adjust the loop's variable capacitor. The software is compatible with Windows and Linux via the Mono framework, offering a graphical user interface for monitoring system status, SWR, power, and motor commands. Key components include one or more magnetic loop antennas equipped with DC or stepper motors for capacitor adjustment, an SWR meter with data output (such as the Telepost LP-100A or a homebrew serial/USB SWR meter), the AutoCap PC software, and a motor interface. The most effective motor interface utilizes an **Arduino-based controller** with custom firmware, providing precise control over both simple DC motors and stepper motors, and supporting features like motor braking for finer adjustments. The system allows for configurable SWR thresholds, pulse widths, and motor effort settings to optimize tuning speed and resolution. Optional radio integration provides frequency hints, enabling the algorithm to learn the relationship between motor actions and resonant frequency, thereby speeding up initial tuning responses. The software also supports antenna profiles, allowing operators to save and recall specific configurations for different loops, including accumulated frequency hint data.

Magnetic Loop Antennas for The Radio Operator with Limited Space, a two part series of articles on how to construct a magnetic loop antenna, including directions on selecting high voltage tuning capacitor

Schematic diagram and description of a magnetic loop antenna that works from 10 to 20 meters band, made from junk

The early 20th century saw significant advancements in wireless communication, culminating in the first successful transatlantic radio signal. This historical account details Guglielmo Marconi's pioneering efforts, from his initial experiments with electromagnetic waves to his patented wireless system in 1900. It describes the technical challenges of long-distance radio transmission, particularly the prevailing belief that radio waves would be lost due to the Earth's curvature over vast distances. On December 12, 1901, Marconi established a receiving station in Newfoundland, Canada, utilizing a _coherer_ and balloons to elevate the antenna. Signals, consisting of the Morse code letter "S" (pip-pip-pip), were transmitted from Poldhu, Cornwall, England. The successful reception of these faint but distinct signals across **1,700 miles** confirmed Marconi's theories, marking an epoch in communication history. This achievement demonstrated the viability of global wireless communication, paving the way for future developments in radio technology.

Operating magnetic loop antennas requires careful consideration of RF safety, particularly regarding near-field magnetic field intensity. This resource presents calculations for magnetic field strength (H-field) at various distances from a magnetic loop, emphasizing that the H-field is significantly higher than the E-field in the near-field region due to the inductive nature of the radiating element. It provides specific formulas and examples for determining safe operating distances based on power levels and loop dimensions, crucial for compliance with RF exposure limits. The analysis compares calculated H-field values against FCC and ICNIRP maximum permissible exposure (MPE) limits for controlled and uncontrolled environments. It demonstrates that even at QRP power levels (e.g., 5W), the H-field can exceed MPE limits within a few feet of the antenna, necessitating greater separation distances than often assumed for electric field considerations. The practical application of these calculations helps amateur radio operators configure their stations to ensure personnel safety and regulatory compliance when deploying compact, high-Q magnetic loop antennas.

Testing performances of indoor antenna. A comparison of a magnetic loop antenna vs a classic wire dipole done using wsprlite on 30 meters band.

Digital radio mondiale DRM products, measuring tools, Magnetic field probes, RF power meters, Broadband loop antennas, DRM devices and services

Magnetic Loop Antenna for 20/15m with Remote Tuning by George Szymanski

A magnetic loop antenna for the VHF band, featuring a high gain that can be compared to a quarter wave vertical antenna

A NEC Model Comparative Analysis of Physical Orientation and Performance. The small magnetic loop is a useful compromise antenna for limited space and portability. For this reason, the magnetic loop antenna is a practical high frequency antenna solution for the restricted space of apartment dwellers

Antennas and Accessories for Satellite Radio and AM FM HD Short Wave Radio, satellite antenna, shortwave magnetic loops.

Experimentig magnetic loop antennas for VHF and HF by M0UKD

A low-cost SWR meter project based on Arduino that works with AutoCap automatic antenna tuner for magnetic loop antennas

Magnetic Loop antenna for 20 to 80 meters band using home made butterfly condensator kit

This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

Octagonal magentic loop antennas that work from 20 to 10 meters with pictures and efficiency reports by G1KEA

A few pictures of an homebrew magnetic loop RTX antenna project, working from 30 to 12 meters with excellent results

Home-Made Magnetic Loop Antenna for 30 Meters by WA8LMF

Such kind of omnidirectional antenna gives the possibility to be QRV with horizontal polarisation, as commonly used for the CW and SSB section of the 2m band. This actual design shows a 1.3:1 bandwidth of about 150kHz, centered to 144.200MHz.

A considerably shortened Magnetic Loop antenna with performance of a single conductor text book magnetic loop.

A page describing how to setup a magnetic loop antenna with the DIY Magnetic Loop Starter Kit produced by Chamaeleon Antenna. Includes a video and a detailed instructions to setup.

A home made magnetic loop for HF Bands. This small and compact loop is designed to support small power transmissions on HF bands, from 7 MHz to 21 MHz

The Magloop Antenna Calculator was developed to predict the characteritics of a small-loop (aka magloop) antenna, given physical dimensions entered via slider widgets. This magnetic loop antenna calculator works also on most mobile devices, adjusting sliders and calculating dimensions in real time.

Maker of small and compact multiband QRP UltraLight Magnetic Loop Antennas and UnUn transformer for end-fed multiband antennas

The resource, "Conventional Use of Transmission Line," meticulously details the operational principles of transmission lines, emphasizing the Transverse Electromagnetic (TEM) mode of energy transfer. It clarifies that for a line to function purely as a transmission line, all currents must be confined internally, with external fields ideally zero. The discussion differentiates between balanced and unbalanced lines, asserting that while both require equal and opposite currents within the conductors, the key distinction lies in the voltage relationship of each conductor to the surrounding environment. It highlights that a good antenna pattern does not inherently confirm proper feeder balance, and that common-mode currents can lead to RF in the shack and increased noise levels, even without pattern distortion. The article further explains that a transmission line can become a radiating conductor if energy is applied in a non-TEM mode, leading to common-mode issues. It cites classic texts like Jordan and Balmain's "_Electromagnetic Waves and Radiating Systems_" and Kraus's "_Antennas_" to support its definitions of TEM mode operation. The content also explores non-transmission line applications of parallel or concentric conductors, such as _coaxial dipoles_ and _folded dipoles_, which intentionally operate in non-TEM modes for antenna functionality. The author, _W8JI_, stresses that simply measuring equal currents is insufficient to confirm a balanced feeder; phase and voltage balance to ground are equally critical.

The video delves into the fascinating science behind antennas, which are crucial for receiving and transmitting electromagnetic waves. It explains how antennas convert electric signals into electromagnetic waves for transmission, and how they operate through the oscillation of positive and negative charges in dipole arrangements. Practical antenna implementations, such as dipole antennas for TV reception and Yagi-Uda antennas with reflectors and directors, are also discussed alongside modern dish TV antennas with parabolic reflectors for signal processing. It's a comprehensive overview of how antennas work and their significance in communication technology.

A 160 Metre Transmitting and Receiving Thin Wire Magnetic Loop Capable of DX. Designed and Patented by Ben Edginton G0CWT

NJ2X is a licensed amateur radio operator (FCC Amateur Extra) who enjoys casting electromagnetic waves into the ether. NJ2X pursues many aspects of the hobby including chasing DX, participating in mini-DX expeditions, building equipment and antennas, and papering his shack walls with ARRL awards. NJ2X dedicates this amateur radio oriented site to helping others who also enjoy the greatest of scientific hobbies. The site is suitable for all readers - families, the young, and the young at heart.